Power transmission calculator

Pulley Speed & Ratio Calculator

Calculate driven pulley speed, diameter ratio and approximate belt speed. Results are an initial selection aid and must be checked against manufacturer information.

Pulley Ratio, RPM & Belt Speed

Enter pulley pitch diameters and driver speed.

Result will appear here.
Calculation assumptions

Assumes no belt slip and uses pulley pitch diameters. Actual driven speed can vary with belt type, loading, wear and installation tension.